m30 timing chain

[flawdaboi407]

I have a 91' m30 from a 735i, im currently refreshing all the gaskets up on it. I took off the upper timing chain cover to access the cam sprocket so I can remove the head. After taking the upper cover off I found out that the tensioner guard is cracked/chipped and needs to be replaced. I took the head off since it needed to go to the machine shop. Now I want to replace the tensioner guard but I have to remove the crank pulley/crank flywheel? lol... in order to remove the lower timing chain cover. Im scared im going to mess up the TDC when trying to remove that big 36mm bolt. Any suggestions. Thanks.

[E30SPDFRK]

Don't worry about messing up TDC, if you have the head off its wicked easy to set. And that nut is a giant pain in the ass to get off, what kind of tools do you have at your disposal?

[flawdaboi407]

1/2 breaker bar, the thing is keeping it from rotating. Or I can lug the motor to UTI and have the boys take it off.

p.s I have a wire in the chain to keep it on the sprocket, that way I can install it the same way. So it wont matter if I undo it? I did it because the bently said so. THanks.

[E30SPDFRK]

I held a torch on my nut for 5 minutes then went at it with an impact at 150psi and it just barely came off. If you can find some way to hold the crank from spinning, you may be able to get it off, but your best bet would be to bring it to UTI if it's not much trouble.

I'm not sure what you're getting at with the sprocket and chain. If you are changing the guides, change the chain too. Worn or broken guides can make a chain stretch out, and imagine having to get that nut off again once it is in the car.

To get tdc put the #1 piston at its highest point and set the valves so they are both shut with the lobes on the cam pointing up. Kind of hard to describe the head set up, I'll try to get you a pic.

[euroshark]

I wedged two 8" long chunks of 2x4 between the crank and the block while it was laid over on it's side. To hold it steady I had a friend stand on the block and push against the garage roof. It took an 18" breaker bar plus a 4 foot cheater bar slipped over the end of it to break that bastard loose. My recommendation is if you don't NEED to take it off to replace the front crank seal or something that you can't access any other way, leave it alone. You can still get your block 95% clean without touching that thing.

[flawdaboi407]

I cant take the lower timing chain cover off without removing the crank pulley. Thats the thing. I want to replace the tensioner guide and thats the only way... In the bently they talk about a special tool to hold the crank bmw 11 2 220 but I can find it. But I did find bmw 11 2 240 which is the same or maybe the new part no. Anyone used one before? How much, and where.

[peerless]

I used a mapp gas torch to heat up the nut and hit it with an impact. That got it off.

As far as installation, you can buy the crank holding tool from Pelican for $50. It M30 specific only. I do own the M20/M42/M50 crank holding fixture as I do a lot of work on these engines.

I may make my own home brewed tool for the M30 as I am hoping not to have to do another one any time soon.

[flawdaboi407]

I made a tool. I took some flat bar, measured the bellhousing side of the engine, cut it so I can thread two bolts in the bellhousing and two in the flywheels holes. Holds pretty good. Now I need a 36mm socket.

[JoeMadoo]

I like to hear all the different methods for the crank nut.

I used a round piece of wood about 3" x 3" and put it in the number one combustion chamber and bolted the head back on to keep the motor from turnin. Another way is to place a socket between the block inner wall and the crankshaft.

[flawdaboi407]

Still need to try it out...

[Good & Tight]

I borrowed my neighbors 3/4" impact gun with 800ftlbs of torque, it ripped the nut off before you could say "bullshit"

[flawdaboi407]

Man I need to get a bigger compressor! :(

[flawdaboi407]

1/2" breaker bar broke! :( fucking shit. Now I need to figure out how to get it to UTI or Detriot Diesel.